Methicillin-resistant Staphylococcus aureus (MRSA) from horse cases and veterinarians in an equine hospital in Japan

We encountered 7 Thoroughbred racehorse cases with methicillin-resistant Staphylococcus aureus (MRSA) infection, one was surgical site infection after orthopedic surgery and 6 ophthalmic infections, in an equine hospital in Japan during 2020. To evaluate the possibility of transmission of MRSA among cases, veterinarians and other horses, MRSA colonization in veterinarians and horses other than MRSA infected cases in the equine hospital were also evaluated. MRSA was isolated from 9 of 28 veterinarians and 1 of 33 horses other than cases. MRSA isolates from horse cases, veterinarians and horse other than cases were conducted to whole-genome sequences to examine genetic relatedness and characterization.